# Completed demonstration example — instrumented gallery routes

This alternate five-by-five model uses zero-based cells, start 20 and destination 3.

## Original sensor set
15, 16, 11.

Route A: 20 → 15 → 10 → 5 → 0 → 1 → 2 → 3. Prediction: one contact. Trace: one contact at 15.
Route B: 20 → 21 → 22 → 23 → 18 → 13 → 8 → 3. Prediction: zero. Trace: zero. Both routes use seven moves.

## Changed sensor set
21, 22, 23.
Route B now records three contacts; Route A records zero. The earlier records remain labelled with the original pattern.

## Decision
If the objective is minimal recorded contact, Route B fits the original pattern and Route A fits the changed one. If the task is to verify detector observations, a route through the sensor cells may be more useful. Contact is a game event, not automatic failure.

## Reflection
The most useful artefact was the ordered route plus the sensor set, because it made each count reproducible. I avoided treating a once-correct zero as a permanent property of the path. In my own task I would predict before execution and inspect the first disagreement rather than changing the route until an attractive ending appears.

Named output: sensor-route.

## Method to carry forward

Compare route traces against an explicit objective, not an assumed preference for zero contacts.

The assigned map and objective differ. Recompute the relevant count or route cost before selecting an approach.

The complete example explains one defensible approach. In your own challenge, select observations and tests from the supplied rules, keep your prediction separate from the result, and justify both the checks you perform and those you omit.

The chapter investigation and its explained record complete the core method. The scene delivery is an optional extension; it is not evidence of deeper understanding on its own.